This review organises aerosol control technologies for animal agriculture into three categories. The first covers approaches already implemented in livestock production, which is fibrous filtration in the MERV 14 to 16 range. The second covers technologies scaled in industrial and medical settings but not yet standard in agriculture, including ultraviolet germicidal irradiation and ionization. The third covers emerging approaches, among them antimicrobial treated filters and electrostatic precipitation. An electrostatic precipitator prototype showed greater than 99 percent PRRSV removal, comparable to MERV 16.
The categories describe maturity rather than merit. Mechanical filtration occupies the first because it is the approach with field validation behind it, running from the controlled demonstration by Dee and colleagues in 2005 that MERV 14 prevented PRRSV aerosol transmission, through the multi year herd studies of Dee 2012 and Alonso 2013, to the 65 farm review by Desrosiers and Cousin in 2023. The alternatives in the second and third categories are supported by controlled results without the equivalent record in production buildings. The SHIC white paper on ultraviolet light from 2020 makes the same point from the other direction, reporting UVC as efficacious against PRRSV under controlled conditions while dust fouling and uneven exposure limit field performance.
For a producer evaluating an alternative to mechanical filtration, the question worth asking is which category a claimed result belongs to. A removal efficiency measured on a prototype in a laboratory is a real result about a real device, and it is not yet a statement about what that device does on a barn inlet across a filter change interval. The technologies in this review are worth tracking, and the ones with production records are the ones a system can currently be designed around.